Fuel pump for internal-combustion engines



Dec. 9, 1930' FUEL PUMP FOR INTERNAL COMBUSTION ENGINES Filed May 29,1929 2 Sheets-Sheet '1 Fig. 1

v J. BENES 1,784,170

J BENES Dec. 9, 1930.

FUEL PUMP FOR INTERNAL COMBUSTION ENGINES Filed May 29, 1929 2Sheets-Sheet 2 dfBenefi" Patented Dec. 9, 193i) UNITED STATES KJOSEFBENES', OF VSETIN, CZEGHOSLOVAKIA i FUEL PUMP FOBINTERNAL-COMBUSTION ENGITVES Application filed May 29,1929, Serial No.367,108, and in Great Britain March 12, 1928.

7 This invention relates to a fuel pump with apre'ssure pump and adistributor, which in this form can be employed for a multi-cylinder oilengine with self-ignition, the regulat- 6 ing of the fuel injected beingaffected with a preferably conical rotating valve, and the ore of which,during each revolution, trav-. els over two recesses orgrooves providedin two rotatable valve saddles, through which 10 recesses the fuel"under pressure escapes back into the suction chamber. Not only thequantity of fuel but also the advancement of the injection admits ofbeing regulated by means of the rotatable saddles.

By this invention the result is obtained that earlierorlater injections(advanced ignition) and also the exact quantity of fuel injected with adefinitely adjusted advance ignition can be regulated by the position ofthe two rotatable valve saddles. The quantity of fuel is regulated bythe two radial bores of the rotating valve coming simultaneously intocommunication with the recesses in the two-rotatable saddles, thedelivery chamber of the fuel pump being connected with the suctionchamber, so that upon the valve bore moving over the saddle recesses thedelivery pipe is relieved of pressure, owing to the fuel flowin intothesuction chamber. r On the other han when, during the turning of thevalve, the mouths of the valve bores leave the recesses in the saddlesand bear upon the ground conical surface of the-saddles, the pressurefuel cannot escape into the suction chamber, and'it flows to the nozzle.The injection time also,

01 the diminution in volume of the compression spaces, can be adjustedby corresponding rotation of the two rotatable saddles relatively to oneanother. Besides this, by joint rotation of the two saddles, theadvanced ignition can be adjusted with a definitely regulated quantityof fuel injected.

The invention'also has the advantage that by the construction of thepreferably conical distributor the result is obtained thatonly one pump,in conjunction with a distributor, is employed for operating a motorwlth any number of cylinders; and it may be emphasized that the pump anddistributor operate with precision, owing to the fact that the reguthatby this construction any inexactitude is lating apertures are located onthe surface of the conical valve plug, whereby faultless sealing isobtained, which on the other hand is self-evident with a conical valve.The device also has the further advantage that the distributorcontaining the regulating mechanism already mentioned automaticallypasses the pressure naphtha or other fuel into the individual cylindersin the injection periods, as necessitated by the method of working of amulti-cylinder engine. so that by this means one distributor inconjunction with one pressure pump suflices for operating amulti-cylinder engine. p

From what has been stated above it is ob- .vious that by this inventionall the sensitive or delicate parts are eliminated from the fuel pump,the piston can if desired be made satisfactorily fluid-tight on bothsides, and the distributing mechanism is arranged on the coni-' calvalve face of its saddle, whereby perfect scaling is obtained. Owing tothis, the pump maintains the high pressure that isnecessary for thecomplete atomization of the fuel, so

eliminated, and the pump does not lose its accuracy even after long use,since the distributing mechanism is the conical valve and saddle, whichform anoil-tight seal even after wear.

The invention is illustrated by way of example in the accompanyingdrawings, in which a Fig. 1 shows a sectional elevation of the pump andthe distributor.

Figs. 2, 3, 4 and 5 show cross-sections of the regulating anddistributing mechanisms on the lines 2-2, 3-3, 4-4 and 5-5 respectivelyin Fig. 1, and

Figs. 6 and 7 show further cross-sections on the line 33 in Fig. 1 withthe saddles and the valve plug in different positions.

Fig. 1 shows a pump 1, having a differential piston 2, which delivers ateach stroke a quantity of fuel proportional to the difference in area ofthe upper and lower pistons. The piston 2 is moved by a; connecting rod4 and a. crank 5 mounted on a. shaft 6. On the same shaft is mounted atoothed bevel wheel '1, which meshes with a similarl toothed bevel wheel7 secured to the sha 10o 8 of a distributing valve 8. The rotation ofthe valve is therefore dependent upon the speed of the pump 1 andtherefore upon the speed of the engine, the transmission ratio of thebevel wheels 7, 7 being determined according to the number of enginecylinders. The valve 8 revolves in a valve saddle 12, in the frameworkof which are inserted two regulating saddles 10 and 11, which arerotatable relatively to one another and also both at once, and also asaddle 9, which carries the fuel delivery pipes to the individualcylinders. This saddle 9 is not rotatable ,but is firmly secured to themain saddle framework. The space 25 is a fuel-storage chamber. Fuel issupplied to the chamber 25 from a main fuel tank through an aperture orduct 26. The valve .8 is pressed on to the saddle 9, 10, 11, 12 by a'spring 27. The pump 1 is connected with the main saddle framework 12 ofthe distributor by means of a member 13, which is screwed into both, andwhich contains a small suction valve 16, which serves as an air outletvalve or vent. This valve 16 is positively actuated in such a way thatit opens even before the termination of the delivery or feeding strokeof the pump 1 and closes after the end of the suction stroke, just whenthe air venting begins, and it does this by virtue of the fact that atthe commencement of the delivery stroke the fuel is discharged throughthis valve and passes through a bore or duct 24 into the storage chamber25. The mechanism for opening this valve is not shown in the drawings,as it does not form part of the subject-matter of this invention.

The drawing illustrates b way of example the arrangement of t e pump anddistributor for a two-cylinder engine working on the four-stroke cycle.The pump act's in the following manner When the piston 2 sucks fuel intothe com pressor chamber 28, at the commencement of the delivery stroke,and only for a short time, the valve 16 still remains open, and thefuel, together with any air or vapor forced in, escapes through thisvalve into the storage chamber 25. Obviously the fuel can also Duringthe advance of the pump piston, and,

the ores 19 and 20 and the bore 21 or 22.

owing to the rotation of the valve, the valve bores 21 and 22 aredisconnected from. the

escape into the storage chamber 25 through in communication with therecesses 35 and 36 until a fresh injection period occurs, which, in thecase under consideration, always occurs after half a revolution of thevalve, since when the pump is executing one revolution, the valve 8executesd alf a revolution, as the engine has two cylinders. Thisoperation is illustrated in Figs. 3 and 4. Now if the regulating saddles10 and 11 are rotated together in such a way that their recesses moveout of the position shown in Fig. 4:, into the position shown in Fig. 6,the valve bores 22 and 21 now leave the recesses 35 and 36 earlier, orin other words there arises anearlier diminution in volume of thedelivery spaces and therefore also an earlier injection and advancedignition.

Now if in the case of Fig. 6 the single regulating saddle 11 or 10 isrotated in such a way that it comes into the position shown in fulllines in Fig. 7, with a given advanced ignition, the quantity of fuelinjected is reduced to about-one half, since, as.will be obvious fromFig. 7, the bore 21 comes into communication with the recess 36 in thelower regulating saddle 11 before the bore 22 comes into communicationwith the re cess 35 in the upper saddle 10, so that through the recessin the lower saddle the naphtha under pressure already escapes upon thevalve being rotated through an angle, (1 It is clear that 11 may haveany value from zero to a, that is to say, the quantity of fuel injectedcan be regulated from zeroupto a maximum value, and from a maximum downto zero, this being done merelyby rotating the saddle 1O relatively tothe saddle 11, whereas by joint rotation of the two saddles out of theirmean position, the ad Vance ignition is adjusted. The distributing ofthe fuel under pressure to the individual cylinders is illustrated inFig. 2. Since the example illustrated relates to a two-cylinder engine,the distribution saddle 9 is provided with two outlet pipes 14 and 15for conveying the fuel under pressure to the individual nozzles. In thisfigure, besides the bore 23, further radial bores are provided, whichare shown as being separated by angles of 120. These three bores are forthe purpose ofrelieving the valve of the radial pressures. In otherrespects the action is obvious from the drawing itself.

The supplying of fuel to the rotating valve 8 is effected by providingthe valve saddle 12 or the Valve plug itself with a recess 01 groove 37round the entire periphery, as shown in Fig. 5, so that the bore 19 isin uninterrupted communication with the recess 37,

so that the bores 19 and 20 are always conary, without going outside thescope of the invention.

The valve may be made cylindrical instead of conical and the otherdetails for carrying the invention into effect may be modified withoutdeparting from the spirit of the invention. I also wish it to beunderstood that the invention may also be applied for use in place ofthe carburettor in internalcombustion engines for automobiles andaeroplanes.

What I claim is 1. A fuel pump for multi-cylinderinternalcombustionengines working with self-ignition and with fuel injection without thehelp of air, comprising a single pressure pump in combination with afuel distributor capable of supplying fuel to the nozzles of the variouscylinders and having a stationary saddle, a revolvable valve plug withinthe said saddle and an annular passage between the saddle L and thevalve plu and the valve plug having an axial bore an radial boresleading from the said axial bore to the said annular assage and radialbores leading to the nozz es, and in further combination with a pumpdelivery chamber with which the said axial bore is in open communicationand with means for revolving the valve 'plug for establishingan opencommunication from the said axial bore to the various injection nozzlesin-turn, as set forth.

v axial bore an 2. A fuel pump as claimed in claim 1 and in which themeans for establishing an open communication between the pump deliverychamber and the axial bore in the valve plug comprise a completecircumferential passage 7 between the stationary saddle and the revolvable valve plug, a passage leading from the said circumferential passageto the pump dehelp of air, comprising a single pressurepum incombination with a fuel distributor capa le of su plying fuel to thenozzles of the various cy 'nders and having a stationary passage to thewhereby the beginning and end of the injeo tion can be adjusted by anadjustment of the movable saddles relatively to one another in acircumferential direction;

single pressure pump and the rotary saddles and the latter having radialpassages in open communication with the said fuel storage chamber andthe segmental passages between the rotary saddles and the valve plug, asset forth.

In testimony whereof I have signed my name to this specification.

J OSEF BENES.

saddle, two saddles within the stationary saddle and capable of rotatingrelatively to thelatter, a valve plug within the saidstationary androtatable saddles, a complete circumferential passage between thestationary saddle and the valve lug and segmental passages between thesaid the valve plu and the valve plug having an d radial bores leadingfrom the circumferential and segmental passages to the said axial boreand from the latter to the nozzles of the various cylinders, whereby theregulation of the fuel injected can be effected by adjusting theposition of the rotary saddles relatively to the stationary saddle andtwo rotary saddles and

